Nothing is more arbitrary and changeable over time, or regarded as more self-evident and absolute in their moment, than social mores. In my own fleeting half-century, I’ve watched mores shift (and, long after them, with tectonic slowness and resistance, laws) until the landscape of the past has become unrecognizable.

Twenty-first century kids will never know the dreamy peace of lying on the shelf beneath the rear window of the car, looking up through the shield of glass at the stars. When I was in grade school, we sometimes played an unsanctioned game at recess called “Smear the Queer” (less offensive/more self-explanatory regional variant: “Kill the Guy with the Ball”). When a student brought what he said was a bomb to high school, Mr. Trautwein, our biochem teacher, told him to quit being an idiot and confiscated it. I grew up to see school massacres become a fad, and binary gender become passé; to see cutesy Christmas cards from boring married gay couples, and marijuana gummy bears. As Robert Stone wrote in his last novel, Death of the Black-Haired Girl: “That which was unspeakable may thrive and is blessed. That which was tolerated is an abomination.”

I’ve always been bemused by the condescension of the present toward the past: the presumption that we, by virtue of our birthdays, are more enlightened, humane, empathetic, somehow better than those incomprehensibly evil people who came before us. Today’s passionate young radicals, through no fault of their own, get to see themselves become tomorrow’s irrelevant old reactionaries. Each generation is shaped and defines itself by its struggle, and so inevitably becomes married to the thing it opposed.

And so each generation regards the last with contempt, and the next with incomprehension.

For example, boomer and Gen X feminists had to be tough to survive in a man’s world, and knew that complaints would only get them banished from it; they learned to take abuse and harassment and condescension, ignore it, brazen it out, or joke their way past it. To them, millennial feminists look like whiners and tattles who revel in their victimhood. Millennial feminists, who’ve learned that their word can destroy CEOs or movie stars, wonder why the older generations put up with that bullshit for so long — to them, they just look like doormats or collaborators. We come to regard what are merely adaptive strategies, contingent on our era, as absolute values. And so each generation regards the last with contempt, and the next with incomprehension.

I can’t help but wonder: what are we doing, every day, that will look just as incomprehensibly evil in a thousand, five hundred, or even fifty years? Why will they hate us in the future?

With the caveat that anyone who purports to predict the future inevitably ends up looking stupid, there are some obvious answers:

They’ll probably be sorta mad at us for blowing through the planet’s resources in just a couple of generations, like teenagers decimating the liquor cabinet in a single unsupervised weekend binge. Or for rendering the Earth inhospitable to human life for the next hundred thousand years, not out of ignorance or stupidity — we’ve known about the warming effects of carbon in the atmosphere for a hundred years — but just because we wanted to own cool things and drive everywhere. Or for the holocaust of the Anthropocene — exterminating hundreds of thousands of species who’ve lived on this planet for aeons, including plants that might’ve been cures for Parkinson’s, Alzheimer’s, or cancer. For these and other heedless crimes against our descendants, animals, and the planet, we may be judged no more leniently than the neighbors at Birkenau.

They may also be appalled by the elaborate fantasies to which we frantically devoted our attention while the world was burning down around us. Our uncritical addiction to the internet will probably look about as cool as those children of the 1950s drooling and stupefied by the tube. And, thinking back on cultural milestones, like Amos ’n’ Andy or The Jazz Singer, now discreetly airbrushed out of our history, I have to wonder what what seems to us like innocent fun that’ll someday be disowned. The fact that the hero of so many of our stories was always a white guy, and the black guy his wisecracking sidekick, will seem as obviously an artifact of a racist society as Leni Riefenstahl. (I confess to hoping that the battles between Inspector Clouseau and Kato will survive the purge.) And I sometimes wonder whether it’s possible to imagine a future when our countless posters of movie stars posing with guns will look about as heroic as the rampant Klansman who graced the poster for Birth of a Nation.

The circle of inclusion — who’s granted equal citizenship, full humanity — has been gradually expanding throughout history (sporadic reactionary contractions like the current one notwithstanding), and it seems fair to extrapolate it will continue to encompass more and more people — perhaps even what we call “things.” What if mores evolve until it’s considered self-evident that animals feel and fear just as much, are as deserving of empathy and compassion, as human beings? Will our descendants buy the defense that we, uh, just didn’t know any better? Could we not hear the screaming in the slaughterhouses, the lobsters clanging at the lid? Didn’t the condemned shit themselves with terror in the abattoirs? How, they’ll wonder, did we ever convince ourselves that the animals we ate and wore and tortured had inner lives and personalities any less complex than the ones we doted on and spoke to and mourned?

Still, it’s easier for me to imagine a future when we’re denounced for our cruelty to animals than one in which we’re held accountable for our perfectly sensible rationales for abusing or neglecting our fellow human beings. Novelist Brian Morton wrote in a recent essay: “When we’re texting or using social media, we don’t tend to be troubled by the thought that the cobalt in our phones may have been extracted by 10-year-olds in Katanga working 12-hour shifts for a dollar a day.”

I can’t even blame the insulating effect of globalization for my own complicity in the economy of cruelty. Last week, walking home in New York City, I passed a man asleep or passed out (but probably not dead) in a wheelchair, a puddle of urine beneath him. This sort of abject squalor is as common a sight in New York as rats or cabs; I felt the usual passing throb of pity/guilt/disgust and kept walking. I hope that someday people will be enlightened enough to despise me for this. I hope it’ll be unfathomable how we all apparently accepted that it was okay and made sense for some people to have literally millions of times more money, power, comfort, and freedom — and could afford to live longer — than others.

Sometimes the world looks like one vast, uncontrolled Stanford Prison Experiment.

We maintain and police these economic boundaries between individuals as fearfully, and lethally, as our national borders. Financially, I am Norway; that guy was the Congo. Lots of (older, richer) people still mock and patronize you if you even try to imagine any system superior to free-market capitalism, which has gutted civil society and laid waste to the world. In her speech at the National Book Awards, Ursula K. Le Guin compared capitalism to the divine right of kings; I like to believe that it’ll someday look like just as transparent a scam. We can only hope that members of a saner society will look back on us the way we do at citizens of the Communist bloc: as dupes or captives of a brutal ideology, rather than true believers or active collaborators.

The corollary of my fear that this great country will someday look like a bellicose, patriarchal police state— a fat Sparta — is the hope that it’ll look that way to a saner, more humane civilization, a space-age Athens. But perhaps, as a writer who’s putting his dwindling hopes on posthumous recognition, I place too much faith in posterity. Aren’t I just projecting my own ethical wish list onto some vaguely imagined utopia? Isn’t this notion of future generations as some superior moral arbiter sort of like the belief in an afterlife that’ll render ultimate judgment, sort ’em all out? Won’t the people of twenty, or fifty, or even a thousand years from now just be a different bunch of assholes?

Let us posit, for the purposes of this essay, that people are pretty much the same animal in all eras and cultures, and that that animal’s defining characteristic is not intelligence or speech or imagination or tool use but gregariousness. We are herd creatures, eager to fit in, who go along to get along, doing or not doing whatever the people around us approve or disapprove of. In itself, this is nothing to commend or condemn — it’s just the kind of animal we are. Man is less like Rousseau’s primal innocent or Hobbes’ thinly-veneered killer, than a scared, sycophantic middle school kid, willing either to volunteer for the homeless or pick on the crippled kid, if it means people will like him.

Most of us accept, as a given, the crappy world that’s handed us, and gamely play whatever role we’re assigned in it. It’s telling that the only time Frederick Douglass uses the word “dehumanizing” in his autobiography is to describe slavery’s effect on white people. In A Connecticut Yankee in King Arthur’s Court, Mark Twain, who’d also seen slavery firsthand, describes a crowd watching a young mother whipped, making blasé comments about the flogger’s deft technique. “This was what slavery could do, in the way of ossifying what one may call the superior lobe of human feeling,” he writes, “for these pilgrims were kind-hearted people, and they would not have allowed that man to treat a horse like that.” Sometimes the world looks like one vast, uncontrolled Stanford Prison Experiment.

Luckily, our pathetic vulnerability to peer pressure makes us just as susceptible to advancement as depravity. It’s hard to deny that human beings are getting — gradually, grudgingly, and unevenly, not without some genocidal backsliding — better. “Despite all our hideous reversions to the wild state,” Nabokov wrote, “modern man is on the whole a better man than Homer’s man, homo homericus, or than medieval man.” Robert Darnton’s history The Great Cat Massacre examines how human beings less than three hundred years ago thought of strangling pets as innocent hilarity. Even some of the humor in Shakespeare strikes modern audiences as discordantly cruel: romantic lead Benedick promises to think up delightful new tortures for the villain in the happy ending to Much Ado About Nothing. In Cannibalism: Human Aggression and Cultural Form, anthropologist Eli Sagan writes: “For the first time in the history of the world, a large number of people — not just a few moral geniuses — are willing to assert that the idea of human is to be extended to all human beings.”

When, as adults, we’re convulsed with shame and self-loathing remembering something stupid or cruel we said in seventh grade, we’re not really being fair to ourselves; we’re judging our unformed childhood or adolescent selves with the full cognitive development and ethical standards of our adult selves. This is a regrettable side effect of growth and, hopefully, improvement. It’s not a sign of healthy development to renounce your former selves, but to accept them. We’re always most contemptuous of phases we’ve most recently outgrown; perhaps one reason we judge the people of the past so harshly is because we know we’re not far removed from them. Slavery wasn’t that long ago, In his autobiography, Errol Flynn is defensive about having “gone native” while he was knocking around the South Seas — that is, he slept with a nonwhite woman — but offhand about the fact that he’d bought her. At Lyndon Johnson’s father’s funeral, some old veterans turned out to pay their respects dressed in Confederate Gray. Johnson was President when I was born; four overlapping lifetimes connect us to the Civil War.

It would be self-flattering to call our present level of civilization “adult.” We’re more like an adolescent, with the powers of adulthood and the judgment of children. Our present historic moment is the part where we’re peeing out of the sunroof, drunk on the highway, at eighty miles an hour. The best-case scenario is that future civilizations will look back on ours, as we do, from a mature perspective, on our own adolescent selves with a shudder of revulsion, but not without some grudging fondness, feeling grateful to have outgrown that reckless self, mindful of all we’ve learned, and lucky to have survived.